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Stereotypic movement disorder

Photo by: Piotr Marcinski

Definition

Stereotypic movement disorder is a disorder characterized by repeated,
rhythmic, purposeless movements or activities such as head banging, nail
biting, or body rocking. These movements either cause self-injury or
severely interfere with normal activities. Until 1994, the American
Psychiatric Association referred to stereotypic movement disorder as
stereotypy/habit disorder.

Description

Stereotypic movements were first described as a psychiatric symptom in the
early 1900s. Since then, they have been recognized as a symptom of both
psychotic and neurological disorders. They may also arise from unexplained
causes. These movements may include:

head banging

nail biting

playing with hair (but not hair pulling, which is considered the
separate disorder of
trichotillomania
)

thumb sucking

hand flapping

nose picking

whirling

body rocking

picking at the body

self-biting

object biting

self-hitting

compulsive scratching

eye gouging

teeth grinding (bruxism)

breath holding

stereotyped sound production

The precise definition of stereotypic movement disorder has changed over
the past 20 years. Today, it limits the disorder to repetitive movements
that cause physical harm or severely interfere with normal activities.
These movements cannot be better described by another psychiatric
condition such as anxiety disorder, a general medical condition such as
Huntington's disease, or as the side effect of a medication or illicit
drug (for example, cocaine use).

Stereotypic movements occur in people of any age, including the very
young, but they are most prevalent in adolescence. People may exhibit only
one particular stereotyped movement or several. The movements may be slow
and gentle, fast and frenetic, or varied in intensity. They seem to
increase with boredom, tension, or frustration, and it appears that the
movements are self-stimulatory and sometimes pleasurable. The root causes
are unknown.

Stereotypic movements are common in infants and toddlers. Some estimates
suggest that 15–20 percent of children under age three exhibit some
kind of rhythmic, repetitive movements. Certainly thumb sucking and body
rocking are common self-comforting mechanisms in the very young. This type
of repeated movement is temporary, and usually ends by age three or four.
It is not the same as stereotypic movement disorder.

It has also been suggested that inadequate caregiving may cause the
disorder. Although many situations can give rise to stereotypic movements,
the root cause of stereotypic movement disorder is unknown. Different
theories propose that the causes are behavioral, neurological, and/or
genetic. Although there are many theories to account for this disorder, no
hard evidence clearly supports one line of reasoning or specific cause.

Symptoms

Symptoms of stereotypic movement disorder include all the activities
listed above. It should be noted that many of these activities are normal
in infants. They usually begin between five and 11 months, and disappear
on their own by age three. In fact, about 55% of infants grind their
teeth. These passing phases of repetitive movement in infants are not the
same as stereotypic movement disorder. They do not cause harm, and often
serve the purpose of self-comforting or helping the child learn a new
motor skill.

People with stereotypic movement disorder often hurt themselves. They may
pick their nail cuticles or skin until they bleed. They may repeatedly
gouge their eyes, bite or hit themselves causing bleeding, bruising, and
sometimes, as in the case of eye gouging or head banging, even more severe
damage. Some people develop behaviors such as keeping their hands in their
pockets, to prevent these movements. In other cases those who hurt
themselves appear to welcome, rather than fight, physical restraints that
keep them safe. However when these restraints are removed, they return to
their harmful behaviors.

Demographics

Stereotypic movement disorder is most strongly associated with severe or
profound mental retardation, especially among people who are
institutionalized and perhaps deprived of adequate sensory stimulation. It
is estimated that 2–3% of people with mental retardation living in
the community have stereotypic movement disorder. About 25% of all people
with mental retardation who are institutionalized have the disorder. Among
those with severe or profound retardation, the rate is about 60%, with 15%
showing behavior that causes self-injury.

Stereotypic movements are common among children with
pervasive developmental disorders
such as autism, childhood degenerative disorder, and
Asperger's disorder
. These movements can also be seen in people with Tourette's disorder or
with tics. Head banging is estimated to affect about 5% of children, with
boys outnumbering girls three to one, although other stereotypic behaviors
appear to be distributed equally between males and females. Despite its
association with psychiatric disorders, there are some people with normal
intelligence and adequate caregiving who still develop stereotypic
movement disorder.

Diagnosis

Stereotypic movements are diagnosed by the presence of the activities
mentioned above. Young children rarely try to hide these movements,
although older children may, and the first sign of them may be the
physical harm they cause (bleeding skin, chewed nails). Often parents
mention these repetitive movements when the physician takes a history of
the child.

The difficulty in diagnosing stereotypic movement disorder comes from
distinguishing it from other disorders where rhythmic, repetitive
movements occur. To be diagnosed with stereotypic movement disorder, the
following conditions must be met:

The patient must show repeated, purposeless motor behavior.

The patient must experience physical harm from this behavior or it must
seriously interfere with activities.

If the patient is mentally retarded, the behavior must be serious enough
to need treatment.

The behavior must not be a symptom of another psychiatric disorder.

The behavior must not be a side effect of medicinal or illicit substance
use.

The behavior must not be caused by a diagnosed medical condition.

The behavior must last at least four weeks. The disorder may be
classified as either with self-injurious behavior or without self-harm.

This definition of stereotypic movement disorder rules out many people who
show repetitive movement because of autism or other pervasive
developmental disorders. It also rules out those with obsessive-compulsive
disorder, where movements are apt to be ritualistic and follow rigid rules
or patterns. In addition, specific disorders such as trichotillomania
(hair pulling) do not fall under the
diagnosis
of stereotypic movement disorder, nor do developmentally appropriate
self-stimulatory behavior among young children, such as thumb sucking,
rocking or transient pediatric head banging.

Treatments

There are few successful treatments for stereotypic movement disorder.
When the patient harms himself, physical restraints may be required. In
less severe situations, behavioral modifications using both rewards and
punishments may help decrease the intensity of the behavior. Drugs that
have been used with some success to treat stereotypic movement disorder
include
clomipramine
(Anafranil),
desipramine
(Norpramin),
haloperidol
(Haldol) and
chlorpromazine
(Thorazine).

Prognosis

Stereotypic movements peak in adolescence, then decline, and sometimes
disappear. Although
behavior modification
may reduce the intensity of the stereotypic movements, rarely does it
completely eliminate them.
Stress
and physical pain may bring on these movements, (which may come and go for
years), especially among those patients with severe mental retardation.

Prevention

Stereotypic movement disorder cannot be prevented. Interventions should be
done to prevent self-injury.

User Contributions:

I met someone who says she rocks. She has good intelegence, motor function, no signs of injury and no history of self injury she will admit to. She admitted to having some ocd activities as a child; i.e. checking to make sure all doors in the house were locked and secured before she could fall asleep. She is 21 and has sinse grown out of the ocd activities. Will she grow out of the rocking? She is aware of the rocking and says it makes her feel good and that's why she doesn't want to stop. She says she can stop but will think about it if she makes herself stop. She is taking some anxiety medicine. I don't know too much about her past but she said she grew up in a place where her family were not too supportive and her county is one of the largest meth areas in her state. Her ex boyfriend died from this. Does her rockking and anxiety sound environmental or nerological? I hate to ask but people with this disorder, are they at risk of snapping one day and completely going off the reservation and causing injury to others? She seems very nice but I am not sure if I want to date her.

Hi Joe,
You could be writing about me! I believe my family has a genetic disposition for the movement disorders that we have. My sister and myself rock when lying down (I've done it as long as I can remember). I can stop when thinking about it, but will start again, not realizing I started until someone tells me. I have Restless legs and when put on medicine for it (sinamet) it has worked wonders, I can finally sleep through the night. Interestingly in our family my sister, my dad and I, we all have a thyroid disorder, my brothers do not and they do not have the movement issues that we have.

HI, I LOST WEIGHT DOWN TO 79BLS AND I SLOWLY GAIN WEIGHT, I HAD EPIDSODE OF HEARTBURN AND TOOK ZANTAC 14 DAYS, FELT BETTER. THEN 2 WEEKS AFTER, I WENT TO THE DOCTOR AND I WAS GIVING OMEPRAZOLE CAPSULE: half of week one i started having a weird headache and it was like my brain being pressed on in different areas with on and off of rocking back and forth. Second week i had fast heartbeat, faster repetitive rocking movement uncontrolable, my right leg would jump with the heartbeat, and with the headache muscle pressure. Im better than before and i slightly rockback and forth but now i slow down i have the eye shifting slight and my nerves through the leg i can feel it move like a sway can you help me understand what is this?

Hi,
I have a 4 year old daughter who has normal development and has hit all of her milestones, but she had been hand flapping when she gets over simulated. There is no self harm with this behavior. not sure what to make of it..

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